A site consists of a homogeneous dense silty sand layer of 9 m thickness, which is underlain by an impervious stiff clay stratum. The initial water table was at 4 m depth below the ground level. A pumping test was carried out by pumping out water at the rate of 0.7 m°/min. Observation wells were dug into the ground at 15 m and 50 m distances from the center line of the well. At steady state (i.e., when there was no change in water levels in the observation wells), the water levels in the two wells dropped by 600 mm and 100 mm, respectively. Determine the hydraulic conductivity of the clayey sand layer.

A site consists of a homogeneous dense silty sand layer of 9 m thickness, which is underlain by an impervious stiff clay stratum. The initial water table was at 4 m depth below the ground level. A pumping test was carried out by pumping out water at the rate of 0.7 m°/min. Observation wells were dug into the ground at 15 m and 50 m distances from the center line of the well. At steady state (i.e., when there was no change in water levels in the observation wells), the water levels in the two wells dropped by 600 mm and 100 mm, respectively. Determine the hydraulic conductivity of the clayey sand layer.

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter6: Hydraulic Conductivity

Section: Chapter Questions

Problem 6.15P

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